Recirculated or recycled steam is used in a number of manufacturing processes. For example, in the manufacture of corrugated cardboard and paper, high-pressure steam is used to heat the drums, plates, and other parts of the corrugator machinery to a temperature sufficient to combine the constituents of corrugated paper into a unified whole. After flowing through the corrugator machinery, the exiting exhaust steam is recycled in a closed system back to a return tank and on to the boiler which generates the high pressure steam used to heat the corrugator machinery.
The present invention is directed to an apparatus and system for diverting and using exhaust steam from manufacturing processes to heat local buildings, and thereby reduce heating costs without sacrificing manufacturing efficiency. Although the diversion and use of exhaust steam in accordance with the present invention is described for purposes of example in the context of the manufacture of corrugated paper, one of ordinary skill will readily appreciate the use of this invention in other industrial settings.
As described in greater detail below, the diversion and use of exhaust steam in corrugated paper processes is accomplished by installing a T-joint or similar pipe fitting at a convenient point in the conduit or pipe between the corrugator machinery and the boiler return tank. One path of the T-joint allows the exhaust steam to proceed in the conventional direction to the return tank; the other path, coupled to suitable piping or other conduit, leads to environmental, i.e., commercial or residential steam heating equipment (e.g. radiators or blowers).
An on-off ball valve, steam pressure regulator, steam safety valve, and check valve are installed between the T-joint and the conventional steam heating equipment. When opened, the on/off ball allows the exhaust steam to proceed toward the conventional steam heating equipment. The steam pressure regulator reduces and limits the pressure of the exhaust steam to approximately 5-15 pounds per square inch ("psi") so that it may used for conventional heating purposes. The safety valve prevents the reduced pressure of the exhaust steam from exceeding the level set by the steam pressure regulator. The check valve prevents the low-pressure exhaust steam from flowing backward through the on-off valve and back to the T-joint. After the steam has cleared the check valve and flowed through conventional heating equipment it, too, can be recycled back to the boiler for regeneration and use by the corrugator machinery.